1. Technical Field
The present disclosure relates to an adhesive film and a foldable display device using the same, and more particularly, to an adhesive film having a shock-resistant structure and a foldable display device using the same, and a method of manufacturing a foldable display device.
2. Discussion of the Related Art
Image display devices, which are a core technology in the information and communication age, for displaying various kinds of information on a screen have been developed such that the image display devices are thinner, lighter, and portable and exhibit high performance. In addition, organic light-emitting display devices, which control the amount of light that is emitted from an organic light-emitting layer to display an image, have been highlighted as flat panel display devices, which have lower weight and volume than cathode ray tubes (CRT).
In an organic light-emitting display device, a plurality of pixels is arranged in the form of a matrix to display images. Each pixel includes a light-emitting device, and the organic light-emitting display device includes a pixel drive circuit including a plurality of transistors configured to independently drive the respective light-emitting devices.
Using a self-emitting organic light-emitting device, an organic light-emitting display device does not need an additional light source, and may be realized as an ultra-thin display device. In recent years, therefore, research has been actively conducted into an in-cell touch type foldable display device, which uses an organic light-emitting device and includes a touch electrode array in a light-emitting cell.
A foldable display device includes a flexible substrate, rather than a hard substrate (e.g., glass). The flexible substrate is easily deformed, for example, curved by external shocks. Furthermore, the magnitude of shocks that the flexible substrate is capable of absorbing is small. When shocks are applied to the foldable display device, therefore, the shocks are directly transmitted to a display panel, and thus can cause damage to elements provided in the display panel. To commercialize the foldable display device, which exhibits low shock resistance, it is necessary to improve the shock resistance of the foldable display device. Consequently, much research has been conducted into improvements in the shock resistance of the foldable display device.
Meanwhile, a related art adhesive film used in display devices has low rigidity and hardness. As a result, external shocks are directly transmitted to the display panel via the adhesive film. In a general display device, external shocks may be absorbed by a substrate and a cover glass, even when such a related art adhesive film is used. In the foldable display device, however, it is necessary for the adhesive film to exhibit desired shock resistance.